<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>
	<script src="js/jquery-3.2.1.js"></script>
	<script>
		$(function(){
			$("#btn").click(function(){
				$("div").each(function(index, element){
					if ($(element).is(":visible")) {
						$(element).css("display","none");
					} else{
						$(element).css("display","block");
					}
				})
			})
		})
	</script>
	<body>
		<div style="display: block; color: red;">初始显示</div>
		<div style="display: none;">初始不显示</div>
		<button id="btn">点击</button>
	</body>
</html>
